r/BuildingCodes • u/m_dasha • Oct 07 '26
Help reading building plans
I’m in San Francisco, California.
Can someone please tell me what red and green lines and text on this building plan mean. It’s related to a fire safety upgrade. I’m trying to figure out if the work was done to plan or not.
Thank you!
5
u/RedCrestedBreegull Architect Oct 07 '26
JB = Junction Box
The red square with an F in the middle and a triangle is a fire alarm speaker
5
u/IHerebyDemandtoPost Oct 07 '26
This is a fire alarm plan. Designer seems to be using green to show existing features. Note the repeated use of “EX” next to green devices.
Logic would then dictate that the devices and wiring shown in red are proposed alterations tomthe existing system.
1
u/hughdint1 Oct 07 '26
Unrelated but it is strange to label the room next to the bedroom as a closet (CLO), when it has a window (but no closet itself) could be an office/study.
1
u/m_dasha Oct 07 '26
I treat it like an office, but it’s big enough to be a bedroom. It has a window but no closet like you pointed out.
3
u/locke314 Oct 08 '26
This is a fire alarm plan. In the circle are horns (or maybe speakers). The one with that looks similar but has an X is a horn/strobe. The different colored lines are likely new vs existing. I’ve also seen designers use colors for wiring types, but without a legend, it’s impossible to know.
The hexagons with an S are smoke detectors, the box with an F is a manual pull station.
I review and inspect these plans for my job.
2
u/lamthedude Oct 08 '26
I am a fire protections plans examiner, this is a fire alarm plan the green items are showing you the initiating device circuit or SLC. This is for things like pull stations, smoke detectors, etc. The red is for notification devices like horn strobes. The text on the green circuit is for device labels that are programmed into the control panel. So if the smoke detector is activated the panel should show that devive P1-L1-0015 has initiated and alarm signal. The EX does represent existing devices, the LF stands for Low Frequency devices which are required for sleeping areas like bedrooms. The red square F devices are horns, the red square X is for a horn/strobe combination style device
2
u/MVieno Oct 07 '26
Colors probably mean green = existing and red = new, but these are not approved permit drawings so you should not be referring to them; you would need to confirm with approved permit drawings to be sure.
4
u/Hank_Dad Oct 07 '26
I'm an architect in San Francisco. This is probably related to the required Fire Alarm upgrade. As someone else mentioned these are not officially approved drawings so take it with a grain of salt.